as the preload developed by the tension-application collar torque-off value can overstress, or even fail, the shear head pin.
The HL19 (as noted by UG24U) is a cadmium plated, alloy steel, 100° Flush Shear Head Hi-Lok Pin. The Hi-Lok Pin has a hex recess in the threaded end of the pin that accepts a hex key to facilitate installation (prevent fastener rotation) during torquing of the collar in clearance fit installations (see bottom of page at
which is identified by UG24U as a substitute part for the HL19 Hi-Lok Pin is a 6Al-4V titanium crown flush shear head threaded pin. It does not have the hex recess of the Hi-Lok pin and is intended solely for installation in interference fit installations. While there’s nothing “wrong” with this part, it is not a direct (or even necessarily good) substitution where the HL19PB has been called out…